China's smog has become a major challenge for foreign firms trying to recruit top executives to work in the country, according to the 16th annual AmCham China 2014 Business Climate Survey (the American Chamber of Commerce in Beijing).

According to the survey, 48 percent of the 365 foreign companies that responded said concerns over air quality were turning senior executives away, Reuters reported. That's up from 19 percent just four years ago.

This is not the first time smog has dampened business in China. Smog practically shut down Harbin, a city of around 11 million people, last October. It's also led to widespread flight cancellations, hurt tourism and rendered surveillance cameras in cities useless.

Some have managed to se the opportunity in smog, or at least try. Earlier this year, Chinese billionaire Chen Guangbiao said he would sell cans of fresh air with flavors like "pristine Tibet, post-industrial Taiwan and revolutionary Yan'an" for five yuan (about 80 cents) each.

Kirsten Korosec has written for Technology Review, Marketing News, The Hill, BNET and Bloomberg News. She holds a degree from Northwestern University's Medill School of Journalism. She is based in Tucson, Arizona.
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